The present invention relates to a connecting device for a panic exit door lock and, more particularly, to a connecting device for a concealed-type top or bottom latch for a panic exit door lock that allows easy mounting of the connecting device and that allows adjustment of projection of the top or bottom latch beyond a top face or a bottom face of the panic exit door to allow easy mounting of the lock.
Locks for panic exit doors include horizontal type latches and vertical type latches. Vertical type latches include a top latch and a bottom latch, and the top and bottom latches include a concealed type and a surfaced type according to the way they are mounted. Surfaced type latches are easy to install but can not provide an aesthetically pleasing appearance. Concealed type latches provide an aesthetically pleasing appearance at the cost of difficulties in installation.
FIG. 12 shows a conventional panic exit door 70 including a side opening 702 in an inner side thereof. Door 70 further includes an end opening 704 in each of a top edge and a bottom edge thereof. A panic device or lock 80 is mounted to door 70 and includes an operative device 84, a follower device 82, and concealed type top and bottom latch devices 76 both mounted in an interior space 706 in door 70 and each having a latch 762. A hole or stop is formed on each of a top edge and a bottom edge of a door frame for coupling with latch 762 when door 70 is closed. Each latch device 76 further includes a screw rod 764 having a first end coupled to latch 762 and a second end coupled to an end of a coupling rod 74. The other end of each coupling rod 74 is coupled to a vertical section 724 of a connecting rod 72. Each connecting rod 72 includes a horizontal section 722 extending out of door 70 via side opening 702 and coupled with follower device 82. Operation of operative device 84 causes movement of follower device 82, connecting rods 72, and coupling rods 74 to move latches 762 for locking or unlocking purposes. In practice, connecting rods 72 and coupling rods 74 are inserted via side opening 702 into interior space 706 of door 70 in an inclined angle for installation purposes. Coupling rods 74 are then threadedly coupled to screw rods 764. Such installation is difficult for a single installer. Furthermore, the projections of latches 762 after installation may be more or less and, thus, adversely affect operation of latches 762. In an approach to solve this problem, coupling rod 74 is rotated to adjust a coupling length between screw rod 764 and coupling rod 74, which, in turn, changes the projection of latch 762. However, such adjustment must be accomplished before coupling of connecting rod 72 with follower device 82. Specifically, if the improper projections of latches 762 are found after installation, adjustment can only be carried out after removal of a housing enclosing follower device 82 and after disengaging an end of connecting rod 72 from follower device 82.
Thus, a need exists for a connecting device for a concealed-type top or bottom latch for a panic exit door that allows easy installation of the connecting device and that allows adjustment of projection of the top or bottom latch beyond a top face or a bottom face of the panic exit door to allow easy mounting of the lock.